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Posts Tagged ‘JDK 1.7’

Java Terminologies

September 6, 2009 Leave a comment

 

Few terminologies to be familiar with, before getting started with Java:

 

Java Platform:

The Java platform from Sun allows developing and running programs written in the Java programming language. The platform is not specific to any one processor or operating system, but rather an execution engine called virtual machine and a compiler with a set of standard libraries that are implemented for various hardware and operating systems so that Java programs can run identically on all of them.

The Java Platform consists of several programs, each of which provides a distinct portion of its overall capabilities. For example, the Java compiler converts Java source code into Java byte-code, an intermediate language to be executed by the virtual machine (JVM) and it is provided as part of the Java Development Kit (JDK). The Java Runtime Environment (JRE), complementing the JVM with a just-in-time (JIT) compiler, converts intermediate byte-code into native machine code on the fly. Also supplied are extensive libraries, pre-compiled in which are several other components, some available only in certain versions.

The essential components in the platform are the Java language compiler, the libraries, java language itself (Java API) and the runtime environment in which Java intermediate byte-code “executes” according to the rules laid out in the virtual machine specification. 

  Java Platform

JVM:

The heart of the Java Platform is the concept of a “virtual machine” that executes Java byte-code. This byte-code is the same no matter what hardware or operating system the program is running under. The use of byte-code as an intermediate language permits Java programs to run on any platform that has a virtual machine available. Although Java programs are platform independent, the code of the Java Virtual Machine (JVM) that execute these programs is not so every supported operating platform has its own JVM.

The JVM is a crucial component of the Java Platform. It is a platform-independent execution environment that converts Java byte-code into machine language and executes it. Most programming languages compile source code directly into machine code that is designed to run on a specific microprocessor architecture or operating system, such as Windows or UNIX.

The JVM is an instance of the JRE (Java Runtime Environment) and comes into action when a Java program is executed. JVM can be obtained with JRE / JDK distribution.

Few functionalities of JVM are:-

  • Loading of class files (compiled java source code).
  • Verification of class files i.e., Class files should contain valid byte-code.
  • Interpretation of byte code and then run the program. 

  

JIT: Read more…

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JDK 7 With Danny Coward

 

 

Just recently we had a post about Java versions, and timely SDN has given us a precious insight into JDK 1.7. As Ed Ort candidly speaks to Danny Coward about the venture, Danny reveals few of the new functionalities that will be incorporated in JDK 1.7.

 

Vodpod videos no longer available.

 

Guest Host/Blogger: Ed Ort, Senior Staff Information Engineer, Sun Microsystems
Guest: Danny Coward, Chief Architect for Client Software at Sun Microsystems
August 20, 2009

 

SDN Quotes:

Learn about some of the new and cool features in the next release of the Java Development Kit, JDK 7. In this Deep Dive, Danny Coward, Chief Architect for Client Software at Sun Microsystems, highlighted some of the significant new features in JDK 7. Some of these features focus on modularizing the JDK, supporting non-Java languages at the VM level, and making developers more productive through various small changes to the Java languages. Danny backed up this discussion with some code examples and demonstrations.

 

Few prominent features of JDK 1.7: Read more…